Problems with Pad when constructing girder bridge deck

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PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

I have cracked on with modifying the file to include the missing elements in my previous post. To do so, I realised that if I just tried adding these that I would come a cropper (I don't think I could insert sketches etc in the existing file). In a way, I am very glad I did start again because it answered one of my previous queries in this thread about maintaining symmetry.
Everything was going well until Sketch004. I had wondered how I could easily create a symmetric sketch on the side wall for the panel frames. What I saw in Shalmeneser's file was brilliant, in all my previous attempts I tried to sketch on the faces, thinking this was the way to do it. No wonder most of you thought I was fumbling along :oops: , you were right!. All this gain however exposed another problem - how to pad the sketch correctly on the face I want to attach it to? I modified the padding settings (Direction) to 1.00 0.00 0.00, and chose Symmetric. Do I need to make any other adjustments please.
Sketch005 & Pad005 Query.PNG
Sketch005 & Pad005 Query.PNG (149.27 KiB) Viewed 1157 times
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Deck Rev 5 Sharm_PeterSD.FCStd
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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

:idea:
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Deck Rev 5 _SHALM.FCStd
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PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Fri Jan 21, 2022 9:26 pm:idea:
Thanks for your reply and download.
Unfortunately, I do not have enough information to make proper judgments in isolation.
Your original file has given me great help in making sure I selected the correct axis for the task in hand and I shall continue to use it to complete this bridge section.
This is the sketch from your file that I used to produce my own sketch.
Sketch from reference file.PNG
Sketch from reference file.PNG (22.22 KiB) Viewed 1108 times
.
My sketch and yours are essentially very similar. What I have done wrong is to work with the 3D view which resulted in me using the image above . I thought that there would have been some offsets to move the sketch along the face. I have spent a couple of hours comparing sketches, between your file and mine to find something - but nothing is there.
UPDATE
I have worked very hard to improve my sketches and believe I have done pretty well given my lack of experience. I previously explained my difficulty in the wall section. Fusion and Arrays are things I know nothing about.
The original plan was to complete one module segment, Mirror it over the Y axis and then carry out a Multitransform for the bridge length. in this way, I can avoid using methods i know nothing about..
I really do appreciate your help and perhaps, to save you time, could you please provide some comments on the methods I have used.
Kind Regards
Peter
UPDATE My Computer crashed. I have deleted my reference to your Sketch005 and constraints. Fie OK after re-loading.
Last edited by PeterSD on Fri Jan 21, 2022 11:35 pm, edited 1 time in total.
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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

My last file is symmetric around XZplane.
You should work inside the body independently of what you are doing outside this body. (It will be a problem for later.)

Arch under the bridge will not be symmetric at the future junction ?
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Fri Jan 21, 2022 11:26 pm My last file is symmetric around XZplane.
You should work inside the body independently of what you are doing outside this body. (It will be a problem for later.)

Arch under the bridge will not be symmetric at the future junction ?
Thanks for reply. I had a computer crash and when I re-loaded the file I found the sketch properly constrained - sorry.

I agree that there may be a problem when I mirror. If there is, I shall have to adjust the Linear pattern. The problem I see is that the arch spacings could have been better but I am hoping that the mirroring will just have a bit of distortion. These arches are virtually invisible on the model.
UPDATE
Your comments at the top are VERY wise! I must confess that I have always needed to see the 3D model as I was sketching. It kind of made me feel safer but has also led me astray too often :oops: .
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

At last I think I can now understand why my efforts throughout this thread have been thwarted, The problems I have had have not been about the sketches but really about The method I adopted when Padding. The clue to this is in the picture below showing the YZ axis crossover point running through the centre of the X axis. In my case the same view shows that the Y axis is on the leading edge. This is why I could never get my sketches on the wall to work unless I placed the sketches directly on the 3D Model :cry:
I shall now check carefully my file bearing this in mind.
Your File 3D Model view YZ axis.PNG
Your File 3D Model view YZ axis.PNG (7.07 KiB) Viewed 1038 times
Kind Regards
Peter
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

I have found that my padding error was at the route of the tree, tried correcting and ended up clearing one problem and finding another. This resulted in more issues. Decided that the best way to proceed was to start again and I am pleased I did. I have ended up with a good model with symmetry to the point I was stuck at before, I have also sorted out the Jack Arches by adjusting the length measurement in the LinearPattern to correct for 3.5 arches.
Where I am having trouble now is the side frames, Sketch006.I liked very much the shaped frames that Shalmeneser produced in his model and have tried to use it. I ended up with a fully constrained Sketch but it complained of a broken face. I have ha to fudge this to achieve the sketch but think these are OK. If someone can comment, I would appreciate it. Thankyou.
Deck Rev 5 ,1 Sharm_PeterSD.FCStd
(123.7 KiB) Downloaded 12 times
Kind Regards
Peter
Forgot the Sketch
Panel End Fraes Sketch006.PNG
Panel End Fraes Sketch006.PNG (82.81 KiB) Viewed 971 times
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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

Line (green) in a sketch must be a frontier between inside and outside.
If you have problem to see your sketch, hide function in the tree.

What is the logic for a LinearPattern for Girder but not for Arch ?
PeterSD
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Re: Problems with Pad when constructing girder bridge deck

Post by PeterSD »

Shalmeneser wrote: Sun Jan 23, 2022 10:30 pm Line (green) in a sketch must be a frontier between inside and outside.
If you have problem to see your sketch, hide function in the tree.

What is the logic for a LinearPattern for Girder but not for Arch ?
I have been using this technique to check the shetch with the drawing, to identify broken faces. . I added the line across the Deck Base to give belts and braces before I posted the query above. Rotating the model shows me that I have a anchored the sketch to the body. I am still learning but have found this approach helpful in the past. What is the best way please?
3D View with sketch.PNG
3D View with sketch.PNG (123.37 KiB) Viewed 934 times
I had not thought of using LinearPattern for the Arch. Thining about it now, it may have been better. I calculated the length and incremented a couple of times to ensure the distances matched including the rim on the half arch. I used the ruler in the 3D Tools to measure across faces. The half arch centre line is also vertical to the end of the bridge deck.
Kind Regards
Peter
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Shalmeneser
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Re: Problems with Pad when constructing girder bridge deck

Post by Shalmeneser »

Have you found the 2 solo lines (with T-junction) ?
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